Meiotic and sperm chromosome studies in a reciprocal translocation t(1;2)(q32;q36).
Meiotic and sperm chromosomes were studied in a man heterozygous for a reciprocal translocation t(1;2)(q32;q36). Forty-five meiotic metaphase I cells were obtained from semen samples: 86.6% were 22,XY,IV and 13.3% had synaptic anomalies that affected all or some of the bivalents. The quadrivalents observed had a ring configuration (92.3%) or a chain configuration (7.7%). A total of 105 sperm chromosome complements were analyzed: 41% resulted from an alternate segregation, and the percentage of unbalanced sperm was 59%; most of them (71%) resulted from an adjacent 1 segregation. The frequency of anomalies unrelated to the translocation (5.7% numerical and 14.1% structural anomalies) were within the normal range for control donors. There was a good correspondence between the percentage of cells with a ring IV (92.3%) and the proportion of 2:2 segregations (88.6%) and between the percentage of chain IV (7.7%) and the incidence of 3:1 segregations (11.4%).
Templado
C
C
Departamento de Biologia Celular y Fisiologia, Facultad de Medicina, Universidad Autónoma de Barcelona, Spain.
Navarro
J
J
Requena
R
R
Benet
J
J
Ballesta
F
F
Egozcue
J
J
D002878:Chromosomes, Human, Pair 1; D002889:Chromosomes, Human, Pair 2; D006801:Humans; D007621:Karyotyping; D008297:Male; D008540:Meiosis; D013094:Spermatozoa / Q000648:ultrastructure*; D014178:Translocation, Genetic